This invention relates to cutting devices which can be used for operations such as animal dehorning, cutting of cables and ropes, and cutting of plastic and soft metal when rapid cutting action is required.
Animal dehorning and cutting of thick cables and ropes can be difficult operations to perform using hand-operated shears. Mechanical devices have been developed to facilitate such operations. For example, pneumatically or hydraulically powered dehorners are described in Australian Patent Application No. 54639/90 and Australian Patent Application No. 33895/89, respectively. Australian Patent Application No. 22731/77 discloses a cutting device which can be powered either pneumatically or hydraulically.
Hydraulically powered cutting devices have had the disadvantage that a source of hydraulic fluid must be available. This is usually provided by coupling the device to the hydraulic system of a tractor. Whatever the source of hydraulic fluid, flexible hydraulic lines are used to connect the source to the device. The weight of hydraulic lines when charged with fluid coupled with the weight of the device can compromise the advantage gained by mechanization of the device.
The lighter lines used to connect an air source to pneumatically powered cutting devices and the generally lighter components making up the devices lead to devices which require less effort to operate than hydraulically powered devices. However, known pneumatically powered devices tend to be unreliable under rapid repetitive use conditions and frequently lack the power for efficient cutting in operations such as animal dehorning.
A further disadvantage of both pneumatically and hydraulically powered cutting devices is that specially engineered components are typically required to fabricate devices. This can have an adverse effect on manufacturing costs as components must be made to order rather than being taken from normal stock items.
There is therefore a need for a cutting device, suitable in particular for use in animal dehorning, which takes advantage of the lightness of pneumatically powered devices but overcomes the disadvantages of existing devices. In particular, there is a need for a cutting device which is reliable, is sufficiently powerful for use in operations such as animal dehorning, and can be fabricated from readily available components.